Psychobiology_Exam 4 Flashcards
Involved in:
i. writing and speaking
ii. Memory functions related to emotions/connected to events
iii. Speech production from the Broca’s area
iv. Executive functioning, which controls:
1. Inhibition (self control)
2. Ambition
3. Responsibility
4. Ability to anticpate and evaluate consequences
5. Judgement and insight
b. If it is impaired, a person’s handwriting may change, memory may be affected, abstract thinking, reasoning, and problem solving may all be affected
c. Includes the prefrontal cortex, which receives information from other parts of the brain
d. In all, if the ______ is damage, a person’s personality and planning may be greatly affected
Frontal Lobe
Involved in:
i. Visuospatial processing, understanding maps
ii. Tactile
iii. Language and mathematics
b. If impaired, a person may have tactile and gustatory hallucinations, difficulty reading a map, mathematical difficulty, and/or difficulty coordinating movements
Parietal Lobe
Involved in:
i. Visual function, discrimination, and memory
ii. Facial and object recognition
b. If the _________ lobe is impaired, a person may have visual hallucinations
Occipital Lobe
a. Involved in:
i. Reception of speech as controlled by Wernicke’s area
ii. Memory, learning, and abstract thought
b. If the ________ lobe is impaired, a person may have difficulty comprehending speech, auditory hallucinations, and possibly olfactory hallucinations
Temporal Lobe
a. Involved in:
i. Physiological responses to emotional states
ii. Instinctual drives such as self preservation, aggression, sexual behavior,
Limbic System
Limbic System
b. Functional grouping of several structures; the two main structures are the:
___________
- Responsible for:
a. Converting short term memory into long term memory
b. Emotional responses to memories
c. Hallucinations and flashbacks that may occur with PTSD - Severely damaged in Alzheimer’s
_________
- Responsible for:
a. Primitive impulses like aggression and sexuality
b. Behavioral awareness; helps pattern appropriate emotional and behavioral responses such as fear, sexual desire, rage, and appetite
c. Love and sustaining long term relationships
Hippocampus
Amygdala
a. Involved in:
i. *Reward
ii. Motivation
iii. *Addiction
b. This is the key structure of the brain responsible for reward, motivation, and addiction; drugs such as cocaine and nicotine trigger the release of dopamine from the ventral tegmental area (VTA) and lead to activation of the _______ __________
c. *This part of the brain would be involved in addictions
Nucleus Accumbens
a. Involved in:
i. Survival
ii. Maintaining homeostasis by regulating metabolism, temperature, and emotions
iii. Regulates autonomic, endocrine, emotional, and somatic functions
iv. Controls appetite (feeding, drinking, and satiety)
v. Regulation of stress response, immune system, and sleep/wake cycles
vi. Controls the pituitary in feedback loops
Hypothalamus
a. The relay station in all sensory pathways and filters environmental stimuli to prevent overstimulation of the cerebral cortex
b. Connects cerebral cortex to basal ganglia, hypothalamus, and brain stem
Thalamus
a. Includes the:
i. Midbrain
1. Controls unconscious motor behaviors
- Contains the substantia nigra, which creates dopamine and is involved in Parkinson’s disease
ii. Pons - Relays between cerebrum and cerebellum
iii. Medulla oblongata - Controls heartbeat, blood pressure, breathing, coughing, and swallowing
iv. Reticular activating system - Plays a role in sleep/wake cycle, alertness, concentration, consciousness, and attention
Brainstem
a. Complex of structures including several parts, most importantly the *substantia nigra
b. There are high concentrations of dopamine receptors
c. *The main functions involve initiating and terminating movement
d. This structure can be affected by drugs that block dopamine; if the receptors are blocked, a person may have Parkinson-like movement disorders
Basal Ganglia
Theories
a. Ability of the brain to change in various ways to compensate for loss of function in specific areas; the brain can make new neural connections and can adjust activities and reorganize self
b. Decreases with age as connections are formed
Neuroplasticity (plasticity)
Theories
a. *Repeated stimulation to a neuron results in sensitization of the neuron over time so the neuron then requires less stimuli to produce a response
b. Occurs in PTSD, panic and bipolar
Ex. cortisol produces activity in the amygdala producing a sensitization of those neurons; then, over time, less stress is required to trigger an episode
c. This theory may explain why manic episodes become harder to treat with each successive episode
Kindling-sensitization
Theories
a. Process of removing extra synapses; occurs during adolescence
b. May play a role in Schizophrenia as buffer is removed
Synaptic pruning
Theories
a. Integrates the concepts of environmental stressors and genetic or psychological vulnerability
Diathesis Stress Model
Theories
a. developmental defects in neuron formation and or migration and synapse formation sensitizes the brain to react differently than a normal brain to later stress
b. stress during adolescence triggers abnormal response within brain that initiates and perpetuates injury and concurrent psychosis
Two Hit Theory
Neurotransmitters
a. Affects cerebral cortex, hippocampus, and limbic structures
b. Influences sleep, arousal, pain perception, coordination of movement, and memory acquisition and retention
c. A deficit of ____________ is associated with Huntington’s Disease, confusion, and *Alzheimer’s
d. Excess may be associated with depression
Acetylcholine
Neurotransmitters
a. Created in the substantia nigra, which is part of the basal ganglia
b. Involved in cognitive activity, decision making, attention, motivation, pleasure, purposeful movement
c. Mild excesses
i. Improved creativity, increased generalization, improved spatiality
d. Too much can cause positive symptoms in *schizophrenia
i. Disorganized thinking
ii. Disorganized speech
iii. Non-purposeful movement
iv. Altered sensory experiences (hallucinations)
Dopamine
Neurotransmitters
a. Created in the pons of the brainstem
b. A major neurotransmitter of the sympathetic nervous system, it is involved in the fight or flight response, attention, cognition, memory, information processing rate, fatigue, sleep, heart rate, and blood pressure
c. Low levels
i. Depression
ii. Mental dullness
iii. Slow information processing
iv. Increased fatigue
v. Psychomotor retardation
d. High levels
i. Anxiety
ii. Manic episodes in bipolar
iv. Paranoia
Norepinephrine
Neurotransmitters
a. Synthesized in the brainstem and abbreviated 5-HT, this neurotransmitter is mainly inhibitory and influences mood, sleep cycle, pain perception, sexual interest, regulation of food intake, and the release/activity of other neurotransmitters such as glutamate, dopamine, and GABA
b. Inhibits release of norepinephrine, dopamine, and glutamate
c. Low levels
i. Irritability and hostility
ii. Depression
iii. PTSD
iv. OCD
d. High levels
i. Sedation
ii. Hallucinations
Serotonin
Neurotransmitters
a. A derivative of glutamate
b. Decreases neuronal excitability
i. Decreases arousal, aggression, anxiety, excitation
c. Low Levels
i. Irritability and hostility
ii. Tension and worry
iii. Anxiety
iv. Seizure activity
v. Schizophrenia
d. High Levels
i. Decreased cellular excitability
ii. Sedation
iii. Impaired memory
GABA
Neurotransmitters
a. Excitatory neurotransmitter
b. Necessary for learning
c. In excess it may cause cell death by increasing intracellular calcium (excitotoxicity)
Glutamate
Controlling Amounts of Neurotransmitters
- _____________ are receptors located on a neuron, when stimulated they function in a *negative feedback loop to decrease the amount of neurotransmitter released by the presynaptic neuron they are located on
a. If an _____________ is blocked, too much of a neurotransmitter may be released - ________ is the process by which a neurotransmitter is pumped back into the neuron that originally released it
a. Increasing ________ would decrease the amount of neurotransmitter present in the synapse and therefore decrease the effect of the neurotransmitter
b. Inhibiting ________ would increase the amount of neurotransmitter present in the synapse and therefore increase the effect of the neurotransmitter (ex. SSRIs in depression) - ______ degradation occurs when an ______ in the synapse inactivates the neurotransmitter (ex. acetylcholinesterase is an ______ that inactivates acetylcholine)
Autoreceptors
Reuptake
Enzyme
Causes of ______ _________
- Neurotransmitter amounts (may be increased or decreased, which may be caused by impaired synthesis)
- Transport pumps/feedback mechanism (malfunction of pumps, reuptake, or autoreceptors)
- Receptor malfunctions (may be destroyed, too sensitive, or not sensitive enough)
Mental Disorders
Specific Mental Disorders
a. Long-term mental disorder that involves distortion of thoughts, perception, and emotion as well as bizarre behavior and social withdrawal
b. Genetic and is more common in males
c. Positive symptoms are caused by increased levels of dopamine in the mesolimbic pathway
i. Loose associations
ii. Flight of ideas (talks quickly with some connections between ideas)
iii. Word salad (no connections between words)
iv. Neologisms (creating new words)
v. Word finding problems
vi. Delusions (false fixed ideas)
vii. Ideas of reference
viii. Thought blocking
ix. Thought broadcasting
x. Hallucinations
1. Auditory and olfactory originate in the temporal lobe
2. Visual originate in the occipital lobe
3. Tactile and gustatory originate in the parietal lobe
d. Negative symptoms are caused by a lack of dopamine in the mesocortical pathway; they are behavioral deficits
i. Amotivation/avolition (lack of motivation)
ii. Alogia (poverty of speech)
iii. Anhedonia (inability to experience pleasure)
iv. Asociality
v. Flat or incongruent affect
vi. Attention impairment
e. If the brain is imaged we would see enlarged ventricles, widened sulci, decreased cerebral cortical volume in the temporal and frontal lobes, decreased volume in the limbic system (hippocampus and amygdala), basal ganglia, and thalamus
Schizophrenia
Specific Mental Disorders
a. A common psychiatric problem that is caused by an imbalance in biochemical interactions; the cause seems mainly related to a deficit in the monoamines: norepinephrine, dopamine, and serotonin
i. Since it seems to be caused by a deficit, drugs that increase the levels of these neurotransmitters seem to be the best solution
b. Hormones are not regulated appropriately so people with depression often have high levels of cortisol, high levels of TRH and TSH, and high levels of substance P (a neurotransmitter that is responsible for inducing pain sensations)
Major Depression
Specific Mental Disorders
a. A disorder in which a person has manic episodes, caused by excess norepinephrine, and depressive episodes, caused by depleted norepinephrine
b. Aside from norepinephrine imbalances, there is also dysregulation of serotonin and dopamine
Bipolar
Specific Mental Disorders
a. Can be influenced by traumatic events, stress, and genetics
b. Decreased receptors for GABA and serotonin in the amygdala and hippocampus
c. Increased activation of norepinephrine in brain
d. Specific Types
i. Generalized
ii. ___
1. Anxiety disorder characterized by obsessions (thoughts that are illogical and unreasonable) and compulsions (actions or repetitive behaviors that are performed to decrease the anxiety)
2. Prefrontal hyperactivity, increased frontal lobe activity, and basal ganglia abnormalities
3. Abnormalities in serotonin regulation
iii. _____
1. Discrete episodes of anxiety that occur without warning
2. Possibly triggered by caffeine, nicotine, and lactic acid
Anxiety
OCD
Panic
Specific Mental Disorders
a. Disorder that is a result of experiencing or witnessing a traumatic event
b. Symptoms:
i. Flashbacks (hippocampus issue)
ii. Intrusive thoughts
iii. Hypervigilence
iv. Sleep disturbances
v. Somatic problems
c. Causes changes in the brain:
i. Hippocampus volume decreased
ii. Hyperresponsive amygdala
iii. Increased CRF release
iv. Decreased cortisol
PTSD
a. drugs trigger release of dopamine from the nucleus accumbens
b. High levels of dopamine eventually lead to decreased number and sensitivity of dopamine receptors so it takes more of a drug to achieve the same effect
Addiction
Discrete episodes of increased anxiety - occur without warning
Sudden onset of intense apprehension, fearfulness, feelings of impending doom
Physical symptoms self limiting - decrease within 10 minutes
Chest pain, palpitations, ↑ HR, pounding, trembling
Shortness of breath - smothering sensation
Numbness
Chills or hot flushing
Paresthesias
Diaphoresis
N&V
Panic Disorder
Obsessions which are unreasonable and defy logic
Difficulty concentrating
Marked distress
High levels of anxiety especially if person resists compulsion
Repetitive behaviors that the person feels driven to perform
Interfere with ADL’s
Physical manifestations related to ritual - dermatitis from excessive hand washing
Obsessive Compulsive Disorder (OCD)
Persistent pattern of inattention and/or hyperactivity Problems with executive functioning Inattention Difficulty organizing Distractible Forgetful - poor memory
Difficulty waiting
Impulsive
Abnormalities of the Reticular Activating System
Attention Deficit Hyperactivity Disorder
Brainstem
Contains the substantia nigra, which creates dopamine and is involved in Parkinson’s disease
Pons
Brainstem
Relays between cerebrum and cerebellum
Medulla oblongata
Brainstem
Controls heartbeat, blood pressure, breathing, coughing, and swallowing
Reticular activating system
